The U.S. Embassy in the Turkish capital Ankara said on Thursday that it lifted all restrictions on visa services, after the country fulfilled high-level assurances on detained local embassy personnel, easing a months-long row.

"Based on adherence to these assurances, the Department of State is confident that the security posture has improved sufficiently to allow for the full resumption of visa services in Turkey," the embassy said in a statement.

The statement said the U.S. continued to have serious concerns about the allegations against its employees.

Turkey's lira firmed after the statement to 3.78 against the dollar, its highest level since October 31.

The U.S. partially resumed issuing visas in Turkey after getting assurances about the safety of staff at its missions there early last month, in the first step to ease a diplomatic crisis between the two allies.

The Turkish embassy in Washington said almost immediately it would match the move, announced on the eve of a visit to the United States by Turkey’s Prime Minister Binali Yildirim.

But the U.S. embassy said it remained deeply concerned over the detention of two of its locally employed staff at diplomatic missions in Turkey, and the fate of U.S. citizens arrested under a state of emergency in force since a failed coup last year.